HIV 1 & 2, Ab Western Blot

The HIV 1 & 2, Ab Western Blot test helps confirm the presence of antibodies to human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2) in the blood. It is intended to be used as a specific confirmatory test after the preliminary screening tests, like ELISA, Chemiluminescence assay (CLIA/CMIA) rapid card tests, etc show a positive result. This test is more specific and helps confirm an HIV diagnosis. 

HIV or Human immunodeficiency virus (HIV) causes disease by damaging your immune system and hence interfering with your body's ability to fight infection and disease. It is caused by 2 types of viruses, namely HIV 1 & HIV 2.

HIV is transmitted from one infected person to another through sexual contact, contaminated blood transfusions, shared needles and syringes, and from mother to child during pregnancy, childbirth, and breastfeeding (vertical transmission). If untreated, HIV can progress to AIDS (acquired immunodeficiency syndrome), a potentially fatal condition usually many years after the initial infection. 

Early diagnosis of HIV infection with the HIV 1 & 2, Ab Western Blot test allows for timely intervention, slowing the progression of AIDS and improving the quality of life. Knowing your HIV status helps prevent the spread of the virus to others. Additionally, a confirmed diagnosis through this test guides doctors to make effective, personalized care plans. 

The HIV 1 & 2, Ab Western Blot test is recommended as a confirmatory test or a supplemental test to indicate whether you have HIV-1 or HIV-2 or both viruses in your body. This test is usually not recommended as a screening test for HIV infection in symptomatic or asymptomatic individuals nor should it be used for blood donor specimens. It should be performed if the screening test for HIV (like ELISA, Rapid test, or CLIA/CMIA based) is reported as reactive or indeterminate. A screening test for HIV is usually advised if you have symptoms of an acute or chronic HIV infection, or a high risk of exposure to the virus, such as unprotected sex with multiple partners or sharing needles. Even those not in the high-risk group might choose to be tested to ensure they don't have HIV or to monitor treatment effectiveness. 

The HIV 1 & 2, Ab Western Blot test is crucial because it accurately confirms the presence of HIV antibodies after an initial positive screening test, reducing the risk of false-positive results. It also distinguishes between HIV-1 and HIV-2, two types of virus that require different management and treatment approaches as HIV-2 is less easily transmitted (i.e. less infectious), and progresses more slowly than HIV-1, leading to a lower viral load and slower immunosuppression causing longer asymptomatic stage.

The HIV 1 & 2, Ab Western Blot test is only a qualitative antibody detection test; it does not give any information about the viral load in the body. This test cannot be done in children under 18 months because maternal antibodies can be present in the infant’s blood. These maternal antibodies, passed from the mother to the baby during pregnancy, can lead to false-positive results. Instead, a polymerase chain reaction (PCR) test is used for diagnosing HIV in infants below 18 months, as it detects the viral genetic material directly. 

A duly filled Consent form for HIV testing & Pre-test counseling (Annexure - CR/01) is mandatory at the time of sample collection. 

Lab test results may vary across laboratories. Abnormal test results require an expert interpretation; therefore, never try to self-medicate at home based solely on these results, and always consult a doctor for a proper understanding of the test results. The insights from this test help the doctor tailor an appropriate treatment plan.